How It Works Operating System.

How It Works Operating System.

The name of the operating system best known for PCs based on the Intel microprocessor - MS-DOS - means a record of
Microsoft operating system (Microsoft disk operating system). Originally operating systems were designed only
manage one of the most complex operations of input / output: communication with multiple disk drives. But the system
operational quickly became a full-bridge between the PC and the program runs it.

Without an operating system, every programmer would have to invent, from a sketch, how the program would present the
text and the graphic on the screen, as send data to the printer, read it and record it as files on disk and a series
other functions linking the program to the hardware. However, an operating system does more than make life easier
programmers.

The operating system creates a common platform for all programs used. Without it, you probably would not be
able to write files created in different programs on the same disk, because each would have his own way of
storing such files. The operating system also provides tools to manage all the tasks you want
run outside the application - delete and copy files, see the list of files contained on the disc and perform a series of
commands in a batch file (batch file).

The operating system does not work alone. It depends not only on the cooperation of other programs but the combination
without conflict with the BIOS. As seen in the previous chapter, when some parts of the operating system is loaded from
disk, they are added to the BIOS, joined by device drivers, and they all perform routine functions
hardware. The operating system actually consists of all three components. It is simplistic to think of the system
operating as only the files contained in a disc that came with your PC.

Together, BIOS, device drivers and operating system perform so many functions that it is impossible to show such
complexity in some pages of illustrations. We will present how memory is used by the operating system and give
and a simple example of a typical program using the BIOS service to print a single character.

Source: Evolution of Computers